Problem: Simplify the following expression: $k = \dfrac{3qp - 2p^2}{rp + qp} + \dfrac{3qp - 3rp}{rp + qp}$ You can assume $p,q,r \neq 0$.
Explanation: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{3qp - 2p^2 + 3qp - 3rp}{rp + qp}$ $k = \dfrac{6qp - 2p^2 - 3rp}{rp + qp}$ The numerator and denominator have a common factor of $p$, so we can simplify $k = \dfrac{6q - 2p - 3r}{r + q}$